The present invention relates to emergency installations for supplying breathable gas in an aircraft, the installation having a supply of breathable gas under pressure and a feed pipe for feeding gas to the feed regulators of individual emergency equipments. On airliners, a delivery valve that operates automatically as soon as the user takes hold of the equipment is generally interposed between the pipe and each regulator.
Proper operation of the individual equipments (or at least of those for use by the crew) is verified before each flight on civil aircraft. At present, the verification is performed by taking gas from the on board emergency supply, generally constituted by a cylinder of oxygen under pressure. This method of verification draws off a portion of the supply and requires frequent replacements.